1. Field of the Invention
The present invention relates to a display, and more particularly, to a flat panel display and method for manufacturing the same.
2. Discussion of the Related Art
Up until recent years, cathode ray tubes (CRTs) have been typically used to form display devices, such as televisions or monitors. However, cathode ray tubes are heavy, bulky and require high drive voltages. Nowadays, the use of flat panel displays is increasing because of their advantages of thin profile, light weight and low power consumption. Examples of flat panel displays include liquid crystal displays (LCDs), plasma display panels (PDPs), field emission displays (FEDs), and electroluminescence displays (ELDs) (which are also called electroluminescence devices).
FIG. 1 is a cross-sectional of a related art flat panel display. As shown in FIG. 1, the related art flat panel display 50 includes: first and second substrates 20 and 30 facing each other with a predetermined distance therebetween; first and second arrays 21 and 31 formed on facing surfaces of the first and second substrates 20 and 30, respectively; and a space 25 defined between the first and second substrates 20 and 30. In regard to the above described related art configuration of FIG. 1, the configuration of the arrays 21 and 31 is variable based on characteristics and/or type of the flat panel display. For example, the two arrays may be formed respectively on the substrates or may be formed together on just one of the substrates. Hereinafter, applications of the various flat panel displays as mentioned above will be briefly explained.
Plasma display panels are designed to display an image on a screen based on the principle that when ultraviolet light, emitted by gas filled between the upper and lower substrates, strikes phosphor, a specific visible light is generated corresponding to the type of phosphor. Thus, the phosphor acts to emit light using the ultraviolet light generated during the electric discharge through the gas. The flat panel displays of a plasma display panel are configured such that two glass substrates, each having electrodes, are attached with a predetermined gap therebetween having a plurality of small partitions, and the gap within in each of the partitions is filled with discharge gas, such as Ne or Xe, at a pressure of several hundreds of torr prior to the flat panel display panel being completely sealed.
An electroluminescence display includes: an upper substrate having no array; and a lower substrate having a thin film transistor array, and phosphor adapted to emit light in accordance with operation of the thin film transistor array. The electroluminescence devices are display devices based on the phenomenon of electroluminescence (EL) in that phosphor generates light when an electric field beyond a predetermined level is applied to the phosphor. The electroluminescence devices may be classified into an inorganic electroluminescence device or an organic electroluminescence device (OELD), in accordance with the type of phosphor light source having the excitation of carries.
In particular, the organic electroluminescence device is being recognized as a natural color display device since phosphors in the organic electroluminescence device can display colors throughout the entire visible light range, including blue color. Also, the organic electroluminescence device has several advantages, such as high brightness and low drive voltage, a great contrast ratio by virtue of self-luminescence, ultra-thin displays, and a relatively low environmental contamination due to having a simplified fabrication process. Moreover, the organic electroluminescence device can easily display moving images due to its short response time of several microseconds, and does not have a limited viewing angle. The organic electroluminescence device is stable even at low temperatures, and a drive circuit for the organic electroluminescence device can be easily designed and manufactured because of low drive voltages of DC 5 V to 15 V used in the organic electroluminescence device. Although the organic electroluminescence device has a configuration similar to an inorganic electroluminescence device, the organic electroluminescence device is designed to emit light via recombination of electrons and holes, and therefore, the organic electroluminescence device may be called an organic light emitting diode (OLED). Hereinafter, the term “organic electroluminescence device” will be used.
FIG. 2 is an exploded perspective view of a related art liquid crystal display. As shown in FIG. 2, the related art liquid crystal display includes first and second substrates 1 and 2 affixed to each other with a predetermined gap therebetween, and a layer 3 of liquid crystal molecules formed between the first and second substrates 1 and 2 via injection of the liquid crystal molecules. More specifically, the first substrate 1 has a plurality of gate lines 4 that are arranged in a first direction and a plurality of data lines 5 are arranged perpendicular to the gate lines 4 that define a plurality of pixel regions P. Each of the pixel regions P are provided with a pixel electrode 6. Further, each of the pixel regions P also includes a plurality of thin film transistors T adjacent to where the gate lines 4 and data lines 5 intersect, thereby serving to apply data signals of the data lines 5 to the respective pixel electrodes 6 in response to signals applied to the gate lines 4.
The second substrate 2 includes a black matrix layer 7 for shielding light except in the pixel regions P. Red, green, and blue color filter layers 8 are provided in the pixel regions P to render red, green, and blue colors, respectively. A common electrode 9 is provided on each of the color filter layers 8 to create an image together with the pixel electrodes 6.
In the case of the liquid crystal display having the above described configuration, the liquid crystal molecules of the layer 3 between the first and second substrates 1 and 2 are aligned under the influence of an electric field created between the pixel electrodes 6 and the common electrode 9. Thus, the quantity of light passing through the layer 3 of liquid crystal molecules is regulated based on the degree of alignment of the liquid crystal molecules 3 for the creation of an image. Heretofore, a variety of related art flat panel displays have been described, but these flat panel displays as stated above have the following problems.
All related art flat panel displays employ a pair of first and second substrates facing each other with a predetermined distance therebetween, and the first and second substrates are made of glass. However, these glass substrates, which are about half of the material costs for the flat panel displays, are expensive, resulting in an increase in the overall manufacturing costs of the flat panel displays. Further, the greater the size of the flat panel displays, the greater the cost due to the use of larger glass substrates. Accordingly, it is necessary to develop a material as substitute for one or both of the glass substrates, or other technologies for reducing the manufacturing costs of glass substrates.